It has been found difficult to manufacture a cast cylinder block where the working surfaces of the cylinders are free from fretting and wear. As typical in the art, the cylinder block is counterbored and a cylinder liner is inserted. Over time the cylinder block becomes damaged due to the high loading and component relative motion which is encountered during operation of the internal combustion engine. As a result the joint that holds the cylinder liner in place requires remanufacture. One method of remanufacturing the joint includes re-machining an undercut in the joint of the cylinder block to a pre-determined depth and inserting a ring or shim generally equal to the depth of the undercut. It is critically important that the joint allows the cylinder liner shim to be centrally located and parallel with the cylinder liner bore. One potential source of damage is due to the undercut being rounded at its outer surface and not allowing the ring to sit flat on the joint of the cylinder block. The rounded undercut and ring generally weakens the cylinder block with a non uniform stress concentration. Another potential problem, the rounded surface of the counterbore or undercut generally causes problems with sealing between the cylinder block and cylinder liner.
Various rings have been developed in an attempt to improve the stress distribution of the joint in a counterbored cylinder block. For example, U.S. Pat. No. 3,389,693 to Herschmann discloses a ring that has a cross section whose width to length ratio is at least a 1:1 which supposedly provides a more rigid joint. However, the ring disclosed requires a large undercut to be machined into the cylinder block. In many applications this may not be feasible.
The present invention is directed to overcoming one or more of the problems as set forth above.